In a letter sent to VeloNation, the Dutchman states that he took the decision himself rather than being introduced to EPO by his-then TVM team. He said that he is shocked by stories of organised doping programmes and said that for himself personally, that he didn’t experience such a setup when it came to him beginning to use the blood booster.

“I’ve simply never seen anything like that,” he writes. “My experience was very different. My doping was done by me, and nobody ever forced me. Of course, I always knew it was wrong and was scared of the risks I was taking. And I will always regret what I did.”

De Jongh states that he used EPO ‘on a few occasions’ between 1998 and 2000. He was with TVM for two of those three years, then moved to Rabobank at the turn of the decade. During that time he won races such as the Postgirot Open, the Mijl van Mares, the Henk Vos Memorial, Veenendaal-Veenendaal and the Nationale Sluitingsprijs.

“It was very easy to get hold of and I knew it couldn’t be detected,” he said of the substance. “I was a fairly young rider, the opportunity was there right in front of me and it was a pretty big challenge to stay away from the temptation. There was no pressure at all from my team, the directors or the doctors to take it. This was my choice.”

De Jongh states that he didn’t used banned substances for the rest of his career. Instead, he says that he stopped for several reasons: firstly, that it was wrong, and also because of the various risks including those to his health, to the family he was planning and also of being caught. He said that times were tough afterwards due to the difficulty of the sport, which was still awash with others using EPO and other banned substances, but that the sport gradually became cleaner and he was able to win races as a result.

He won Kuurne-Brussels-Kuurne in 2008, while one year earlier he took a stage of the Tour of Qatar and the GP Briek Schotte. On the basis of his letter, he is stating that those wins were achieved clean.

Three years after his retirement, he said that the moment is right for him to speak out about what happened before. “I’ve always believed that everyone should take responsibility for their own decisions and it’s easy to see that I made entirely the wrong ones in the past,” he wrote. “I made my biggest mistakes a long time ago but I need to admit this so I can move on. I want to stay in this sport but I know that it can’t be with Team Sky. It’s sad to be leaving but there's no other option.”

De Jongh writes fondly of his time with the team but while it is clear that he would like to say, he states that he didn’t consider lying in order to keep his position.

“The discussions going on in Team Sky have given me the chance to be honest about all this. Some might think I could have kept quiet, but this is a good chance for me to talk openly, the best moment to admit my mistakes. It’s time to talk.

“This admission has been a big shock to my girlfriend, family and friends, and I am thankful for all the support they are giving me. After this difficult decision I need to re-establish their confidence in me and to prove to my girlfriend and kids that I can give them the future we want.”

He said that he hopes to remain part of the sport, but knows that he must find an alternative team or role to do so.

It is not clear if others will also end up leaving the team over the zero tolerance policy. Thus far, De Jongh, Bobby Julich, Michael Barry and Sean Yates have walked away, although the latter has said he is doing so for health reasons rather than as any admission of doping.

Steven de Jongh’s letter is as follows:

This is a hard thing to talk about, but I’d like to tell the truth about my experience of doping.

I’ve been shocked by the stories and rumours of organised doping programmes because I’ve simply never seen anything like that.

My experience was very different. My doping was done by me, and nobody ever forced me. Of course, I always knew it was wrong and was scared of the risks I was taking. And I will always regret what I did.

I took EPO on a few occasions from 1998 to 2000. It was very easy to get hold of and I knew it couldn’t be detected. I was a fairly young rider, the opportunity was there right in front of me and it was a pretty big challenge to stay away from the temptation. There was no pressure at all from my team, the directors or the doctors to take it. This was my choice.

I stopped because it was wrong and it wasn’t worth the risks – to my health, to the family I wanted, or of getting caught. The years after I’d stopped doping were sometimes hard. But cycling was slowly getting better and I managed to win races clean. I think the ‘whereabouts system’ and biological passport were great things for this sport.

I’ve always believed that everyone should take responsibility for their own decisions and it’s easy to see that I made entirely the wrong ones in the past. I made my biggest mistakes a long time ago but I need to admit this so I can move on. I want to stay in this sport but I know that it can’t be with Team Sky. It’s sad to be leaving but there's no other option.

I’ve learned a lot at Team Sky and have great people around me. We came into the sport with big ambitions, and I'm proud I was part of building this team. It’s hard to let go but after three amazing years I don’t want a price to be paid later, by me or the team. I don’t want to let these people down.

The discussions going on in Team Sky have given me the chance to be honest about all this. Some might think I could have kept quiet, but this is a good chance for me to talk openly, the best moment to admit my mistakes. It’s time to talk.

I love this sport and it has been a huge part of my life. With the steps we've been taking in cycling there is a better chance than ever to compete in a clean sport. I’m certainly committed to that and everybody I’ve worked with can assure you that's the case.

I truly regret what I did. And I believe it’s important that if you make a mistake you can still get a chance in life. It would be a huge regret if my mistakes of 12 years ago meant I could no longer work in cycling. People might accept and forgive if we can only tell them what happened.

This admission has been a big shock to my girlfriend, family and friends, and I am thankful for all the support they are giving me. After this difficult decision I need to re-establish their confidence in me and to prove to my girlfriend and kids that I can give them the future we want.

I hope very much to stay in this sport, and I’m sure I can play my part in its clean future.